For the most part, free weights have it on machines. They force you to use your stabilizer muscles, allow you to move naturally, and require you to control not just the load being moved, but also the direction (path) of the movement.
That being said, at Performance U Hybrid Strength & Conditioning, we’ve found there are a few exceptions in which machines may be a better bang for your muscle-building buck than free weights. In this article I’m going to share with you 5 machine-based exercises that we’ve found to be more beneficial at increasing muscle size than their free-weight counter-parts.
Not Free Weights vs. Machines, Free Weight + Machines
Before you get your posing trunks in a bunch. Hear this…
The goal of this article is certainly not to convince you to abandon proven free weight exercises and use just machines in your workouts – far from it! The goal here is to help you embrace the special benefits certain machines can offer you that free weights may miss when performing certain exercises.
That being said, from our experience, the best muscle-building programs are those that incorporate BOTH free weights and machines.
With my disclaimer out of the way, let’s talk shop…
1. Preacher Curl Machine
Biceps curls with free weights are super effective at building up your guns, which is why we use them as staple exercises in our arm building programs. However, there’s one disadvantage all free weight and cable biceps curl variations have that a machine doesn’t – gravity!
Here’s a quick biomechanics lesson:
During any style of biceps curl, the point in which the muscle is maximally stimulated, is when the lever arm is at its longest. This occurs when the forearm is at a 90-degree angle with the load vector.
If you're using free weights, gravity is your load vector. Therefore, the point of maximal loading would be when your elbow reaches 90 degrees of flexion or when your forearm is parallel to the floor.
If you're doing biceps curls using a cable column, the cable itself is the load vector. In this case, the lever arm is at its longest when your forearm makes a 90-degree angle with the cable.
Here’s the kicker:
The farther away you move from a 90-degree angle with the load vector, the shorter the lever arm becomes and the less work your biceps have to do. That why, in a free weight biceps curl, the closer you move toward the bottom or top of the range, the less work your biceps get because the lever arm is shortening. That’s precisely why people tend to rest between reps at the top and bottom position when doing barbell or dumbbell curls.
On the other hand, the biceps curl machines is designed with a CAM system, which isn’t dependent on a single load vector like free weights or cables. Instead, the CAM is set up to offer you a much more consistent resistance throughout the entire range of motion. This also gives you much more time under tension because your biceps never get a chance to rest at the bottom or top position.
Sure, you can use a variety of different biceps exercises using free weights and cables to create a maximal force angle at different points in the range of motion. But if you’re short on time, or looking to add in a big bang for your buck move, the preacher curl machine is an exercise that hits the muscle from all points of the elbow flexion range.
Note: keep in mind what you just learned about lever arms and CAM systems because it also applies to exercises 2-4 as well.
2. Reverse Pec-Deck
Ever notice that when most people do rear-delt flyes with dumbbells they end up swinging (cheating) a bit? That’s because if you grab a weight that fits your strength during the initial part of the rear-delt flye, it’s going to be too heavy when you get your arms get to the point that they are parallel with the floor. It is at that point in the movement that your lever arm is at its longest.
However, when you do reverse pec-deck flyes, you don’t have that same issue because the lever arm remains fairly consistent throughout the entire range of motion. Plus, you get resistance right from the start of the exercise as the machine tries to push your hands together. This is an advantage over dumbbells, which do not require you to work hard at the start of the movement because your arms are just hanging there.
This exercise has a lot of the same benefits as reverse pec-deck given that both are inverse motions. When doing pec-flyes using dumbbells, you get the tension at the bottom (stretched) position, but get less and less the closer you come to the top position as your arms move above your shoulders. But when using the pec-deck, you get even tension (due to the CAM system) throughout the entire range of motion – even when your arms are directly in front of your shoulders. This allows you to hit your pecs in a manner that dumbbells don’t allow.
Now, unlike the dumbbell version, cable chest flyes do hit your pecs when you arms are extended out in front of you. But cable flyes don’t give you much tension when your arms are in the stretched position since they’re in-line with the cables, which creates a very short lever (if any).
Again, anytime you are working against a single force vector, you’re going to have ranges within the exercise where the lever arm is long (creating high levels of muscle activation) and you’re going to have ranges where the lever arm is short (resulting in very little activation).
The machines I’ve listed in numbers 1-4 of this article all work on a CAM system that doesn’t limit you to just one force vector. This is the main advantage these machines have over free-weights and the reason we feel they should be utilized.
4. Shoulder Lateral Raise Machine
We’ve found this machine to be more effective at putting on some serious shoulder caps than its free weight counterpart for the very same reason I’ve already shared on the previous three exercises I listed.
Even at the bottom position, when your arms are by your sides, your delts are working against the machine. Whereas in the dumbbell version, your arms are just hanging there and your shoulders are relaxed.
Note: All the machines listed in 1-4 allow you to create more overload and increase the time under tension. Put simply, More time under tension + more overload = more muscle, baby!
5. High Row Machine
We at Performance U like this machine simply because the movement feels very natural and allows you to perform a diagonal/arch-like compound pulling motion.
Think about it, most pulling exercise are either vertically oriented (chin ups, lat pulls, etc.) or horizontally oriented (bent over rows, seated rows, T-bar, etc.) But, the hammer strength high row machine is kind of in the middle. It’s like the incline press for the back. It’s not a bench press and it’s not a shoulder press. It’s somewhere in the middle.
In other words, this machine allows us to hit the back in such a way that’s hard to match with other exercises. And, it give us a little of everything. That’s why, if we’re short on time or had to recommend only one compound pulling exercise to do, we’d advise doing this one because it blends two proven pulling actions (horizontal and vertical) into one comprehensive exercise!
Coaching Tips from the Trenches
With the exception of the high row machine, we’ve found that machines can be most beneficial when performing isolation exercises. In other words, we like to stick with mostly free weights for compound movements. However, we’re likely to sprinkle in some machines when we’re doing less complex, single joint type movements. This is exemplified by the fact that 4 out of the 5 exercises on my list are isolation moves.
Finally, while you can absolutely build plenty of muscle size exclusively using free weights, we don’t see why you would avoid machines if you had access to them. Especially if you understand how to maximize the unique benefits they have to offer.
As I said early in this article, we found the best hypertrophy (muscle size building) programs are the ones that use machines in conjunction with (mostly) free-weights.